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  <title>Document</title>
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  <script>
    //如果箭头函数参数只有一个参数，那么（）可以省略

    var names = ["abc","cba","nba"]
    names.forEach((item,index,arr) = >{
      
    })
    names.forEach(item =>{
      console.log(item)
    })
  
  
  
  </script>
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